As this invention relates to an apparatus for indicating alarms for a magnet wire fabrication process, it is necessary to understand the basics of the process in order to fully appreciate the need and desirability for such an apparatus.
Magnet wire is fabricated with an electrically insulating film (enamel) on metal wire. This wire's end use is in coils which produce electromagnetic fields as found in electric motors, transformers, relays, etc. It is extremely important that enamel film be cured to the proper degree to produce the optimum electrical and mechanical properties.
Much of today's magnet wire insulation is produced in two enamel coats. The base coat is formulated to give optimum electrical insulating properties and the top coat enhanced mechanical properties, such as a low coefficient of friction so that the wire will readily pass through high speed coil winding equipment without film damage.
The wire is produced at high speed and a fast response is therefore required upon detecting an abnormal condition in order to provide quick corrective action and thereby prevent production delays. Magnet wire factories usually consist of a large number of production units spread over a wide expanse and staffed by only by a small number of maintenance personnel on and around the clock basis. An alarming system can be provided for detecting faults and producing verbally annunciated alarms in time to provide sufficient information to immediately direct the maintenance personnel to the source of the problem to prevent production shutdowns.
Sometimes the nature of the problem quickly cascades into other types of problems and a number of such verbal alarms are present almost instantaneously. Interlocks may be provided to prevent none but the first alarm condition to be annunciated. However, although this technique prevents the confusion attendant with more than one verbal message annunciating at the same time, the information relating to the nature of subsequent alarms is lost.